diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index fb17a43575..0b5b3f9d8c 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -80,6 +80,19 @@ jobs:
           docker-compose -f ./docker/cli.yml -f ./docker/cli.assetstore.yml run --rm dspace-cli
           docker container ls
 
+      # Wait until the REST API returns a 200 response (or for a max of 30 seconds)
+      # https://github.com/nev7n/wait_for_response
+      - name: Wait for DSpace REST Backend to be ready (for e2e tests)
+        uses: nev7n/wait_for_response@v1
+        with:
+            # We use the 'sites' endpoint to also ensure the database is ready
+            url: 'http://localhost:8080/server/api/core/sites'
+            responseCode: 200
+            timeout: 30000
+
+      - name: Get DSpace REST Backend info/properties
+        run: curl http://localhost:8080/server/api
+
       - name: Run e2e tests (integration tests)
         run: yarn run e2e:ci
 
diff --git a/scripts/set-env.ts b/scripts/set-env.ts
index 5eee22a4be..b3516ae68f 100644
--- a/scripts/set-env.ts
+++ b/scripts/set-env.ts
@@ -10,7 +10,7 @@ const targetPath = './src/environments/environment.ts';
 const colors = require('colors');
 require('dotenv').config();
 const merge = require('deepmerge');
-
+const mergeOptions = { arrayMerge: (destinationArray, sourceArray, options) => sourceArray };
 const environment = process.argv[2];
 let environmentFilePath;
 let production = false;
@@ -45,10 +45,10 @@ const processEnv = {
 } as GlobalConfig;
 
 import(environmentFilePath)
-  .then((file) => generateEnvironmentFile(merge.all([commonEnv, file.environment, processEnv])))
+  .then((file) => generateEnvironmentFile(merge.all([commonEnv, file.environment, processEnv], mergeOptions)))
   .catch(() => {
     console.log(colors.yellow.bold(`No specific environment file found for ` + environment));
-    generateEnvironmentFile(merge(commonEnv, processEnv))
+    generateEnvironmentFile(merge(commonEnv, processEnv, mergeOptions))
   });
 
 function generateEnvironmentFile(file: GlobalConfig): void {
@@ -65,7 +65,7 @@ function generateEnvironmentFile(file: GlobalConfig): void {
 }
 
 // allow to override a few important options by environment variables
-function createServerConfig(host?: string,  port?: string, nameSpace?: string, ssl?: string): ServerConfig {
+function createServerConfig(host?: string, port?: string, nameSpace?: string, ssl?: string): ServerConfig {
   const result = {} as any;
   if (hasValue(host)) {
     result.host = host;